roberts



(No Model.)

B. P. ROBERTS. INCANDESGBNT ELECTRIC LAMP.

No. 459,100. Patented Sept. 8, 1891.

UNITED STATES PATENT OFFicE.

EDXVARD P. ROBERTS, OF CLEVELAND, OHIO, ASSIGNOR TO THE SXVAN LAMPMANUFACTURING COMPANY, OF SAME PLACE.

INCANDESCENT ELECTRIC LAMP.

SPECIFICATION forming part of Letters Patent No. 459,100, datedSeptember 8,1891.

Application filed July 15, 1891. Serial No. 399,652. (No model.)

To all whom it may concern:

Be it known that I, EDWARD P. ROBERTS, a citizen of Cleveland, in thecounty of Cuyahoga and State of Ohio, have invented certain new anduseful Improvements in Incandescent Electric Lamps; and I do herebydeclare the following to be a full, clear, and exact description of theinvention, such as will enable others skilled in the art to which itappertains to make and use the same.

My invention relates to an improvement in incandescent electric lamps,and more particularly to improved means for connecting the socket-pieceto the bulb.

It is usual in attaching the bulb of an incandescent electric lamp tothe socket-piece to employ plastic material, such as plasterof-paris,Which of necessity must be inserted in the socket-piece in its soft andmoist .condition. The sealing material thus used dries very slowly, andconsequently delays shipment of the goods, and it is also liable tocrack and injure the bulb; and, further, with the use of such moistmaterial the wires which pass through it to the electrodes are liable tobecome injured by the moisture in the sealing material, and in manyinstances in practice it has been found to rust the conducting-wires andcause them to break in the sealing material.

The principal trouble arising from the slow drying of the plaster, asusually employed, is that the wires will be eaten off. This is duelargely to electrolytic action, caused by leakage from one wire to theother, and does not occur to as great an extent if the lamps are notused for a long time after cementing into the cap.

It is the object of my invention to overcome these objections and toproduce a connection between the bulb and socket-piece which will dryquickly.

A further object is to connect the bulb of an incandescent electric lampto the socketpiece in such manner that the sealing substance Will bemade to dry quickly and at the same time avoid the necessity of passingthe conducting-wires through the whole mass of sealing material.

"With these objects in view the invention consists in the combination,with an incandescent electric lamp and a socketpiece, of sealingmaterial for connecting said lamp and socket-piece, and absorbentmaterial adapted to make contact with the sealing material and end ofthe lamp or bulb, and means for retaining said absorbent material inplace.

The invention also consists in certain novel features of constructionand combinations and arrangements of parts, as hereinafter set forth,and pointed out in the claims.

In the accompanying drawings, Figure 1 illustrates an embodiment of myinvention. Fig. 2 is a view of a modification.

A represents an incandescent electric-lamp bulb, and B the metallicsocket-piece, which latter is provided with an opening (L for thereception of the smaller end of the bulb. Inserted in the socket-piece Band made to surround the major portion of the bulb within thesocket-piece is the sealing material I), preferably plaster-ofmris. Theextremity c of the bulb, through which the conducting-wires (I pass, ispreferably made to project beyond the sealing material I). Inserted inthe open end of the socket-piece and adapted to bear on the extremity cof the bulb and against the sealing material Z) is a quantity ofabsorbent material, such as waste or other fibrous material,thisabsorbent material being held in place by a collar 6, preferably ofporcelain, inserted in the open end of the metallic socket-piece. Fromthis construction it will be seen that as the absorbent material willabsorb the moisture in the sealing material and conduct it by capillaryattraction to the open air through the open end of the socket-piece thesealing material will be caused to dry quickly and thus not be liable tocrack; and, further, it will be perceived that as the conducting-wires.do not pass through the moist sealing material they are not subject tothe liability of becoming injured or broken by rust or other cause, towhich they would be subjected were they passed directly through thesealing material.

By the construction and arrangement above set forth the insulationresistance from one wire to the other becomes as light at the end oftwenty-four hours as it does in six days with the use of the waste. Inpractice it is not always absolutely necessary that the lower portion ofcap be filled up to such an extent that the wires will not pass throughthe plas ter, but merely make sure that the plaster will not be in onesolid mass, thereby drying slowly.

Having fully described my invention, What I claim as new, and desire tosecure by Letters Patent, is-

1. The combination, With an incandescent electric-lamp bulb and asocket-piece for receiving the same, of sealing material in thesocket-piece and surrounding a portion of the end of said bulb, andabsorbent material inserted in the open end of the socket-piece andbearing against the sealing material, whereby moisture in the sealingmaterial will be absorbed by the absorbent material and con veyed bycapillary attraction to the outer air through the open end of thesocket-piece, substantially as set forth.

2. The combination, with an incandescent electric-lamp bulb and asocket-piece for receiving the same, of sealing material in thesocket-piece and surrounding a portion of the end of the bulb, absorbentmaterial inserted in the open end of the socket-piece and bear ingagainst the sealing material, whereby moisture in the sealing materialWill be absorbed and conveyed by capillary attraction to the outer airthrough the open end of the Socket-piece, and means for retaining theabsorbent material in place, substantially as set forth.

The combination, with an incandescent electric-lamp bulb and asocket-piece, of sealing material in said socket-piece and surrounding aportion of the end of the bulb, absorbent material in said socket-pieceand bearing on the end of the bulb and against the sealing material, anda porcelain collar inserted in the socket-piece and retaining theabsorbent material in place, substantially as set forth.

In testimony whereof I have signed this specification in the presence oftwo subscribing witnesses.

EDWARD P. ROBERTSn Witnesses:

T. A. BOURDMAN, J12, WM. E. REED.

